Warming suit



Jan. 18, 1966 M. E. GLUCKSTEIN WARMING SUIT 2 Sheets-Sheet 1 Filed Aug.25, 1961 INVENTOR ATTORNEY Jan. 18, 1966 M. E. GLUCKSTEIN WARMING SUIT 2Sheets-Sheet 2 Filed Aug. 25, 1961 INVENTOR ATTORNEY United StatesPatent 3,229,681 WARMING SUIT Martin E. Gluclrstein, Farmington, Mich,assignor to Ethyl Corporation, New York, N.Y., a corporation of VirginiaFiled Aug. 25, 1961, Ser. No. 133,931 17 Claims. (Cl. 126204) Thisinvention relates to a comfort suit. More particularly this inventionrelates to a novel suit by which the human wearer may be kept relativelywarm in cold climates for long periods of time.

Various insulated suits have been proposed by which heavy insulationretains body heat and permits the wearer to endure in a relatively coldclimate. While such suits have achieved some degree of success for shortexposures, the amount of insulation required for long duration is veryhigh resulting in a heavy, bulky, and awkward suit. In extremely coldclimates, say 50 F., the amount of the required insulation may be sogreat so as to make such a suit not feasible for active personnel.

Suits incorporating internal heating by means of portable batteries havealso been proposed. However, the weight of the batteries required andthe low voltage which can be generated at extremely low temperatures areserious handicaps.

It is an object of this invention to provide a novel comfort suit whichwill enable the wearer to endure extremely cold climates for longperiods of time. Another object is to provide a comfort suit ofrelatively light weight which permits the wearer a high degree ofactivity and maneuverability while exposed to extremely cold climates.Another object is to provide a comfort suit incorporating means toutilize the heat generated by a chemical reaction between the breath andat least one chemical.

Still another object is to provide a method of providing heat in acomfort suit to be worn in cold climates.

Broadly, the objects of this invention are accomplished by providing acomfort suit incorporating provisions for a chemical reaction betweenthe exhaled breath and at least one chemical. Heat liberated by thereaction warms the body parts adjacent to the reaction site.Additionally, by utilizing the pressure of exhalation, the warm gaseousreaction products are distributed to the body extremities which arewarmed by the sensible heat of the gases. Further, provisions are madeso that the gaseous products are contacted with catalytic beds locatedat the extremities and other parts of the body. The catalyst promotes areaction with the attendant release of additional heat at the reactionsite.

In another aspect, this invention provides a method of providing heat ina comfort suit to be worn in cold climates which method comprisescontacting exhalation with a chemical capable of reaction with exhaledbreath and transmitting the liberated heat energy to various bodylocations. A preferred method comprises contacting exhalation with ametal hydride, especially sodium aluminum hydride, whereby heat and agaseous product including hydrogen are liberated, distributing saidgaseous product and hydrogen to various body locations, contacting saidhydrogen with an oxidation catalyst whereby an oxidation reaction takesplace with the liberation of heat and transmitting the liberated heat tovarious body parts.

More specifically, the objects of this invention are accomplished byproviding a comfort suit comprising a helmet, a face mask attachable tosaid helmet and equipped with gas inlet means, an enclosed chambercontaining a chemical capable of reaction with exhaled breath, saidchamber communicating with said face mask whereby due to the pressure ofexhalation, breath is Patented Jan. 18, 1966 caused to contact and reactwith said chemical within said chamber to generate heat and a gaseousproduct, a garment capable of being joined to said helmet, said garmentcontaining distribution means in communication with said enclosedchamber whereby the gaseous products of said reaction are distributed tovarious body locations and subsequently discharged to the atmosphere.

A preferred embodiment comprises a helmet, a face mask attachable tosaid helmet and equipped with gas inlet means, an enclosed chambercontaining a metallic hydride, said chamber communicating with said facemask whereby due to the pressure of exhalation, breath is caused tocontact and react with said hydride within said chamber to liberate heatand a gaseous product including hydrogen, a garment capable of beingjoined to said helmet, said garment containing distribution means incommunication with said enclosed chamber whereby the gaseous productsincluding hydrogen are distributed to various body locations andsubsequently discharged to the atmosphere, an oxidation catalystattached to said garment in various locations whereby contacting saidgaseous product including hydrogen with the catalyst results in anoxidation reaction with the attendant release of heat.

The objects and advantages of my invention will become apparent from thefollowing description, in conjunction with the annexed drawing, in whichpreferred embodiments are disclosed.

FIGURE 1 is a diagrammatic view showing a preferred embodiment of a facemask in accordance with my invention.

FIGURE 2 is a diagrammatic representation of a Warming suit inaccordance with my invention, wherein heat is generated by reaction ofexhalation with a chemical, and wherein heated gases are conveyed to theextremities of the body of the wearer due to the pressure of exhalation.

FIGURE 3 is a diagrammatic view of a warming suit according to myinvention wherein the heated gases formed as above are distributed tothe extremities by means of tubular connecting lines and are therepassed through or over catalytic beds wherein an oxidation reactiontakes place to generate more heat.

In FIGURE 1, 1 is the face mask housing, 2 is a supporting shoulder, 3is a one-way atmospheric air inlet valve, 4 is a canister, 5 is aone-way canister inlet valve, 6 and 7 are chemicals, 8 is a tubularconnecting line, and 9 is a manually adjustable control valve. In FIG-URE 2, 10 is the face mask, 11 is a helmet, 8 is a tubular connectingline, 12 is a garment, and 13 are perforations in the garment. In FIGURE3, 14 are tubes and 15 are catalytic beds; 1, 8, 10, 11, 12, and 13 arethe same as in FIGURE 2.

Referring to FIGURE 1, as the wearer breathes in, air enters the facemask through one-way atmospheric inlet valve 3 and is inhaled. Due toits own pressure, the exhaled breath enters canister 4 through canisterinlet valve 5 and is contacted with one or more chemicals 6 and 7. Achemical reaction takes place between the chemical and at least onecomponent of exhaled breath to release heat. Part of the liberated heatis used to warm the incoming air and the wearers face and head. Thegaseous effiuent from the canister, composed of unreacted gases whichhave been warmed by passage through the reaction zone and any gaseousreaction products which will also be at higher temperatures, is thendistributed through line 8 to provide heat to any desired body location.Manually adjustable control valve 9 is provided to enable the wearer tocontrol the amount of exhaled breath entering canister 4. By openingcontrol valve 9, the exhaled breath by-passes the reaction zone 3thereby reducing the quantum of the reaction and the liberated heat.

Referring to FIGURE 2, the warmed gases exit from the canister intotubular connecting line 8 and are discharged beneath air-tight garment12 in the chest region.

Due to the pressure of exhalation, the gases will travel to .the fourextremities and there be discharged through perforations 13 to theatmosphere. The sensible heat content of the circulated gases is used towarm the various body parts.

In the embodiment portrayed in FIGURE 3, air enters the face mask andexhaled breath is contacted with a metal hydride in canister 4 in asimilar manner as previously described. The products of the reaction areheat, hydrogen, hydroxides, and the unreacted constituents of exhaledbreath. The gaseous reaction products are distributed to the extremitiesby means of tubular connecting lines 8 and 14 and are passed throughcatalytic beds 15 where an oxidation reaction between hydrogen andoxygen takes place with the attendant release of heat. The resultingproducts are discharged to the atmosphere through perforations 13.

The present invention provides a comfort suit having many advantagesover those proposed by the prior art. The products of exhalation arecaused to enter into a chemical reaction to liberate heat and hydrogen,and the pressure of the exhalation is utilized as the driving force todistribute gaseous products. The hydrogen is contacted with a catalystand is oxidized to yield additional heat. Thus, a positive heat sourceis provided rather than merely utilizing heavy insulation to retainnormal body heat as suggested with some prior art comfort suits. Also,heavy batteries are not requiredless than one pound of certain chemicalsbeing sufficient to satisfy daily requirements. Moreover, the heatenergy generated by the reactions is directly utilized, thus prvidingmaximum efliciency. Other advantages are that the suit is of relativelysimple design and has no moving parts. The exhaled gases, after reactionwith a metal hydride, are essentially bone dry, thereby precluding watercondensation in the distribution system. Part of the heat liberated bythe chemical reaction can be utilized to heat the incoming atmosphericair thus permitting the wearer to inhale relatively warm air. Thecomfort suit is relatively light affording the wearer maximumflexibility and movement. Moreover, the suit is attitude insensitive andthus functional irrespective of the orientation of the wearer, be ithorizontal or vertical.

Many variations in the construction of the comfort suit are possiblewithin the scope of this invention. For example, the purpose ofatmospheric air inlet valve 3 is to allow one-way flow of air from theatmosphere into the mask and to act as a seal when the air is exhaled.Any appropriate mechanism to achieve this purpose is applicable. One-waycheck valves such as flapper valves, ball valves, etc. are useable.Canister inlet valve is similar to valve 3 and any of the aforementionedoneway valves may be used. The function of canister 4 is to contain thechemical in a somewhat compact form and to be a reaction chamber. It maybe constructed of any material which is not reactive with the containedchemical and the products of reaction. To optimize heat transfer to theincoming air, it is preferable that a material having a high thermalconductivity be used. To further facilitate the warming of incoming air,a fin design may be incorporated and/or the incoming atmospheric air maybe bafiied around the canister to increase the heat transfer area. Thecanister may have compartments to contain several different chemicals.Although not necessary, it is preferable that the canister be mounted inthe face mask and in a manner so as to be easily replaceable with a newcanister. Similarly, a quick disconnect coupling should be utilized toconnect line 8 with the canister. Although the canister has been shownas an integral part of the face mask, other locations such as the loweror upper chest area are possible. However, as will be hereinafterdiscussed, the reaction site must be located near enough to the wearersmouth so that the water vapor of the exhaled breath will not condense inthe distribution system.

Line 8 may also be an integral portion of the helmet and the gaseousproducts may be discharged beneath the garment at the junction where thehelmet and garment are joined. The helmet may terminate and be joinedwith the garment at the neck region or it may terminate at the shoulderregion and there be joined with the garment.

The helmet and garment can be constructed of light, insulated materialso as to minimize heat transfer from the body to the atmosphere and yetallow a maximum degree of flexibility. These units are preferably, butnot necessarily, air tight. The garment may be one integral unit of thecoverall type covering the four extremities, or gloves and boots may beused. The garment may also be two or more separate units which arejoined at the waist or neck regions etc. In the latter cases, the unitsmust be joined in a manner so as to minimize air leakage. The variousunits may be joined in a conventional manner such as incorporating aslide fastener with covering flaps to minimize gas and heat loss. Theextremities of the garment have small perforations to discharge thegases to the atmosphere. The number and size of the perforations at eachof the extremities are varied depending upon the location of the exitgases from line 8. For example, if the gas is discharged under thegarment in the chest region, to facilitate uniform distribution, theperforations on the hand areas are smaller and/or less in number ascompared to the perforations at the feet areas.

An air-tight inner garment may be used as an insulation between the bodyand the distributed warm gases. In this embodiment gas flow will bebetween the garment and the inner garment.

In the preferred embodiment portrayed in FIGURE 3, a tubulardistribution system conveys the gas stream to the four extremities andoptionally to other parts of the body. The gases are passed throughcatalytic beds located at each of the extremities and oxidation of aportion of the gases is promoted. Additional heat is released at thereaction site. The catalytic beds comprise tubular containers filledwith catalyst and may be attached to the underside of the garment or thecatalyst beds may comprise a pocket in the suit which contains thecatalyst. Alternatively, a catalytic material may be impregnated on thesuit proper over relatively large areas, thereby providing heat energyof lower intensity but having a wider distribution. The resulting gasesincluding the water vapor formed by the oxidation reaction may befurther distributed over the body, but preferably are discharged to theatmosphere at the reaction site.

A consideration of prime importance is that any water vapor in thesystem must be kept from condensing. Since temperatures at some pointswithin the suit would be below 32 F., any condensed water vapor wouldform frost or ice. Condensation can be prevented by maintainingtemperatures above the dew point of the gas stream or by eliminating thewater content therefrom. Thus, if the chemical reaction contemplated forproduction of heat does not require water as an essential reactant, adrying agent such as KOH, NaOH, A1 0 MgO, CaO, CaCl etc. can beincorporated into the face mask. The dried gases are then fed to thecanister to react with the chemical contained therein. Under theseconditions, water condensation is precluded and the canister may beplaced in other locations such as the upper or lower chest areas, etc.

In a preferred embodiment, water vapor is one of the essentialconstituents entering into the chemical reaction. To preclude watercondensation, the temperature of the exhaled breath must be kept aboveits dew point and, therefore, the canister must be located relativelyclose to the mouth.

The same considerations are applicable to the gaseous products resultingfrom the chemical reaction. If water vapor is a product, a drying agentshould be incorporated into the system to preclude condensationdownstream from the reaction. In the preferred embodiment of thisinvention, a metallic hydride reacts with the water vapor content of theexhaled breath thereby producing an essentially bone dry gaseousproduct. Thus, additional or special water absorbing means are obviated.

One of the features of this invention is that exhaled breath is causedto react with at least one chemical so as to liberate heat and/or agaseous product capable of being oxidized to liberate additional heat.The approximate composition of the exhaled breath is 15 percent oxygen,4 percent carbon dioxide, 5 percent water, 75 percent nitrogen, and 1percent argon and other constituents. Under resting conditions,approximately 500 cubic centimeters of air are inhaled .15 times perminute. Thus, a minimum of approximately 0.2 pound of oxygen, 0.08 poundof carbon dioxide, and 0.04 pound of water per hour are available toreact with a chemical to produce heat and/or gaseous products. Ofcourse, during periods of activity, greater amounts of these componentsare available.

The heat required to permit the human wearer to endure in cold climatesvaries over a wide range dependent to a major degree on the atmospherictemperature. Accordingly, a variety of chemicals may be utilized in thecomfort suit of this invention to provide the heat required in any givenenvironment. Broadly, any chemical capable of reaction with the oxygen,carbon dioxide, and Water constituents of the breath or any combinationof these to yield heat and/ or a gas capable of being oxidized may beutilized. The chemical should preferably be a solid so as to minimizeany possibility of leakage. It should be capable of entering into areaction of moderate rate without any tendency toward explosiveness orpyrophoricity. The reaction should preferably yield gaseous or solidproducts and the products should be free from any toxic or noxiouscharacteristics.

A class of chemicals possessing many of these properties are the alkalimetals and the alkaline earth metals, the oxides, peroxides, andhydroxides of these metals. Of this group, the metals lithium, sodium,and calcium, oxides such as calcium oxide and barium oxide, peroxidessuch as sodium peroxide and barium peroxide and hydroxides such aspotassium hydroxide, sodium hydroxide and calcium hydroxide arepreferred. These materials react with one or more constituents of thebreath at moderate rates and do not generate noxious products. Thesematerials may be used singly or in combination.

Water vapor reacts with the above described metals to yield hydrogen, ahydroxide, and heat and reacts with the metal oxides to yield heat andthe hydroxide. The hydroxides react with carbon dioxide to yield thecarbonate and heat. The peroxides react with water vapor to yieldoxygen, 9. hydroxide, and heat.

Another group of compounds useable to generate heat are metal alloys.These include alloys of metals such as lead, bismuth, antimony, tin,etc., with an alkali or alkaline earth metal. Typical examples arealloys of sodium and lead, bismuth and sodium, calcium and lead, etc.The particular com-position of the alloy may be formulated so as toobtain the desired rate of reaction, eliminate any possibility of apyrophoric reaction, etc. The alloys react with water vapor to yieldheat and hydrogen, and hydroxides.

Organic anhydrides can also be used. Compounds such as phthalicanhydride react with water vapor to yield the acid and heat.Additionally, a second compound, for example a metal oxide can beutilized to react with the acid in the presence of moisture to yield thesalt and additional heat.

In many of the above enumerated reactions, the generated hydrogentogether with oxygen which is generated by the reaction or contained inexhalation, may be circulatcd to various body locations and therecontacted with an oxidation catalyst. The ensuing oxidation reactionliberates additional heat.

It has been estimated that about 200 B.t.u.s per hour, appropriatelydistributed to various body arts, are adequate to maintain human lifeunder extremely cold conditions for long periods of time. Thus, in apreferred embodiment, the chemicals that can be used in this inventionare those capable of reaction with any of the constituents of breath toliberate at least 200 B.t.u.s per hour, or those liberating a loweramount of heat plus a gaseous product which can be oxidized to liberateadditional heat. In other words, the sum of the heat released during theoriginal reaction and that liberated from oxidation of the gaseousproduct is preferably at least 200 B.t.u.s per hour.

The preferred chemicals useable in this invention are those which arecapable of hydrolysis with the attendant release of heat and hydrogen.The gaseous product resulting from such a reaction will be essentiallybone dry and water condensation problems are precluded. Broadly, anysimple or complex hydride capable of reacting with Water vapor isuseable as the chemical of this invention. The preferred hydridesinclude those of the alkali and alkaline earth metals including lithium,sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium,strontium, barium, etc. and bi-metallic hydrides including the alkalimetal and alkaline earth metal hydrides of boron and aluminum such aslithium borohydride, sodium borohydride, potassium borohydride, calciumborohydride, lithium aluminum hydride, calcium aluminum hydride, sodiumaluminum hydride, potassium aluminum hydride, etc. Of these, the alkalimetal hydrides of aluminum in; cluding lithium aluminum hydride, sodiumaluminum hydride and potassium aluminum hydride are preferred. Thesecompounds show a very high degree of reactivity with water vapor andyield maximum amounts of hydrogen per pound of hydride. The mostpreferred compound is sodium aluminum hydride. This compound is stable,relatively easy to manufacture, and in large quantities is one of themost inexpensive compounds per pound of liberated hydrogen.

In the preferred embodiment, the exhaled breath is caused to contactsodium aluminum hydride contained in canister 4. A hydrolysis reactiontakes place with a release of approximately 2630 B.t.u.s and 2-6 ft. (32F., 1 atm.) of hydrogen per pound of hydride. Hydrogen is generated as aproduct according to the following overall reaction:

The sodium hydroxide and aluminum hydroxide are retained in the canisterand hydrogen, in addition to the oxygen, carbon dioxide, and nitrogenportions of the entering gas stream, constitute the gaseous reactionproducts. No carbon monoxide in detectable amounts is produced by thisreaction. Part of the liberated heat is used to warm the incoming airand the face and head. Catalytic beds are incorporated into the garmentat each of the four extremities and if desired on the chest, back, andtrunk areas of the body. By means of the tubular distribution system,the gaseous product including hydrogen is caused to contact the variouscatalytic beds. The hydrogen and oxygen portions of the gas stream enterinto an oxidation reaction with the attendant release of about 300B.t.u.s per cubic foot of hydrogen oxidized. The gaseous productsincluding water from the oxidation reaction are discharged to theatmosphere.

With this preferred embodiment, one pound of the hydride fully reactedwith the water Vapor of the exhaled breath provides about 2630 B.t.u.sas the heat of hydrolysis and 7800 B.t.u.s from the oxidation of theliberated hydrogen for a total of about 10,430 B.t.u.s. By adjustment ofcontrol valve 9, the quantity of water vapor available for reaction andthus the rate of hydrogen and heat liberation can be controlled and amoderate amount of heat can be supplied to the various body parts over arelatively long period of time. Under resting conditions, approximately0.04 pound of water is exhaled per hour. This amount of water reactedwith the hydride liberates about 80 B.t.u.s as the heat of hydrolysisand about 0.8 cubic foot of hydrogen which when oxidized releasesapproximately 240 B.t.u.s. Thus, under the least favorable conditions,an excess of 200 B.t.u.s per hour are available for distribution tovarious body parts. As the wearer performs any activity, greater amountsof exhaled water vapor are available adding to the quantum of thereaction with the attendant release of larger amounts of heat andhydrogen. For environments demanding an extremely large amount of heat,provisions can be made for introducing water from an external source orfor utilizing other body fluids.

Any of the well known catalysts capable of promoting the oxidation ofhydrogen may be used. These include catalysts with the active agentbeing a metal or metal oxide such as vanadium, copper, chromium,manganese, cobalt, nickel, palladium, platinum, etc. A highly eificientcatalyst which is preferred for this reaction incorporates platinum asthe active agent. Platinum catalysts are generally supported on carriermaterials such as alumina, magnesia, silica gel, asbestos, metallicwires, diatomaceous earth, etc., and usually contain from about 0.01 to3.0 percent of platinum. Methods of preparing such catalysts are wellknown to those skilled in the art.

The approximate stream compositions at various points throughout thesystem are as follows:

Point One Three The approximate temperature of the exhaled .breath is 35C., the temperature of the gases in the face mask after reaction withsodium aluminum hydride is about 50 C., and the temperature of the gasstream after reaction with the platinum catalyst is approximately 100 C.

For the hydrogen gas concentrations contemplated by this invention, theoxidation reaction produces relatively moderate temperatures with noactual flames or glow being produced. The gaseous products from both thereaction in the canister and the oxidation reaction of the hydrogen arenon-toxic. For most situations, the composition of the gaseous streamcontaining hydrogen is outside the limits of inflammability, thusproviding for maximum safety. To maximize distribution of gaseousproducts, small pumps or fans driven by natural body movements such aschest expansion during breathing, arm and leg movements during walking,etc. may be used. I The comfort suit of this invention may also be usedto provide heat to personnel exposed to a variety of environments. Forexample, the suit may be used to provide heat to underwater divers usingportable selfcontained or stationary air sources. In such anapplication, the canister containing the metal hydride is incorporatedinto a water-tight face mask or helmet. Exhaled breath is used to reactwith the hydride and the warmed gases are circulatedbeneath awater-tight garment or through tubes to various body locations. Also,catalytic beds may be incorporated into the extremities or.otherlocations of the water-tight garment to permit the oxida tion ofhydrogen .to yield additional heat. Alternatively, provisions may bemade for reacting seawater with the hydride in an external hydrogengenerating unit. The hydrogen together with the exhaled breathcontaining oxygen is then contacted with the catalytic bed. Rather thanusing exhaled oxygen, the hydrogen may be mixed with air from the diversair tank and passed to the catalytic bed appropriately located.

Methods for preparation of the chemicals used in this invention are wellknown to those skilled in the art. See for example, Inorganic Chemistryby R. B. Heslop and P. L. Robinson, Elsevier Publishing Company, NewYork, 1960; and Inorganic Chemistry by T. Moeller, John Wiley and Sons,Inc., New York, 1952,; and US. Patents 1,958,012; 2,567,972; and2,920,935.

I claim:

1. In a suit adapted to be worn in cold climates and incorporatingprovisions to utilize a chemical reaction involving exhalation toprovide heat and produce an oxidizable material, a garment, means forcontaining an oxidation catalyst attached to said garment, an oxidationcatalyst positioned within said catalyst-containing means, and means todeliver said oxidizable material to said catalyst.

2. A method of providing heat in a suit adapted to be worn in coldclimates which method comprises contacting exhalation with a metalhydride whereby a heated effiuent gas containing hydrogen and oxygen isliberated, distributing said effluent gas to various body locations,contacting said effiuent gas with an oxidation catalyst whereby anoxidation reaction takes place with the liberation of heat, andtransmitting the liberated heat to various body parts.

3. A suit comprising a face mask equipped with breathing gas inletmeans, an enclosed chamber containing a metal hydride capable ofliberating hydrogen in the presence of moisture, means to conveyexhalation from said face mask to said chamber, a garment, means toconvey elfiuent gas from said chamber to said garment, and an oxidationcatalyst attached to said garment and connected with said eflluent gasconveying means.

4. A suit comprising a helmet, a face mask adapted to be attached tosaid helmet and equipped with breathing gas inlet means, an enclosedchamber containing a metal hydride capable of liberating hydrogen in thepresence of moisture, means to convey exhalation from said face mask tosaid chamber, a garment adapted to be joined to said helmet, means forconveying effluent gas from said chamber to said garment, means forcontaining an oxidation catalyst attached to said garment and connectedto said effluent conveying means, and an oxidation catalyst positionedwithin said catalyst-containing means.

5. In a suit adapted to be worn in cold climates and incorporatingprovisions to utilize a chemical reaction to provide heat, a face maskequipped with breathing gas inlet means and exhalation outlet means, anenclosed chamber containing a metal hydride capable of liberatinghydrogen in the presence of moisture, means for conveying exhalationfrom said exhalation outlet means to said chamber, a garment, means forcontaining an oxidation catalyst attached to said garment, means forconveying effluent gas from said chamber to said catalyst-containingmeans, and an oxidation catalyst positioned in said catalyst-com tainingmeans.

6. A suit comprising a face mask equipped with breathing gas inletmeans, an enclosed chamber containing sodium aluminum hydride, means forconveying exhalation from said face mask to said chamber, a garment, andmeans for conveying effluent gas from said chamber to said garment.

7. A suit comprising a face mask equipped with breathing gas inletmeans, an enclosed chamber containing sodium aluminum hydride, means forconveying exhalation from said face mask to said chamber, a garment,means for conveying effluent gas from said chamber to said garment, andan oxidation catalyst attached to said garment and connected with saidefliuent gas conveying means.

8. A suit comprising a helmet, a face mask adapted to be attached tosaid helmet and equipped with inlet gas heating means, an enclosedchamber containing sodium aluminum hydride, means for conveyingexhalation from said face mask to said chamber, a garment adapted to bejoined to said helmet, means for conveying eflluent gas from saidchamber to said garment, means for containing an oxidation catalystattached to said garment and connected to said efiiuent gas conveyingmeans, and an oxidation catalyst positioned within saidcatalyst-containing means.

9. In a suit adapted to be worn in cold climates and incorporatingprovisions to utilize a chemical reaction to provide heat, a face maskcomprising a face mask housing, breathing gas inlet means and anenclosed chamber attached to said housing, said chamber containingsodium aluminum hydride, said chamber being equipped with exhalationinlet means and effluent gas outlet means.

10. In a suit adapted to be worn in cold climates and incorporatingprovisions to utilize a chemical reaction to provide heat, a face maskequipped with breathing gas inlet means and exhalation outlet means, anenclosed chamber containing sodium aluminum hydride, means for conveyingexhalation from said face mask to said chamber, a garment, means forcontaining an oxidation catalyst attached to said garment, means forconveying efliuent gas from said chamber to said catalyst-containingmeans, and an oxidation catalyst positioned in said catalyst-containingmeans.

11. A method of providing heat in a suit adapted to be worn in coldclimates, which method comprises reacting exhalation with sodiumaluminum hydride to form a heating efiiuent gas, and transmitting saidefiiuent gas to vari ous body locations.

12. A method of providing heat in a suit adapted to be Worn in coldclimates which method comprises reacting exhalation with sodium aluminumhydride whereby a heated eflluent gas containing hydrogen and oxygen isliberated, distributing said efiiuent gas to various body cations,contacting said efliuent gas With an oxidation catalyst whereby anoxidation reaction takes place with the liberation of heat andtransmitting the liberated heat to various body parts.

13. A method of providing heat in a suit adapted to be Worn in coldclimates which method comprises contacting exhalation with a chemicalcapable of reaction with exhaled breath, said chemical being selectedfrom the group consisting of alkali metals, alkali metal hydrides, andalloys of alkali metals with metals selected from the group consistingof lead, bismuth, antimony, and tin, to form a heated effluent gas,contacting said eflluent gas with an oxidation catalyst whereby anoxidation reaction takes place with the liberation of heat, andtransmitting the liberated heat to various body parts.

14. A suit comprising a face mask equipped with breathing gas inletmeans, an enclosed chamber containing a chemical capable of reactingwith exhalation to produce a heated effluent gas therefrom, saidchemical being selected from the group consisting of alkali metals,alkali metal hydrides, and alloys of alkali metals with metals selectedfrom the group consisting of lead, bismuth, antimony and tin, means toconvey exhalation from said face mask to said chamber, a garment, meansto convey said heated efiiuent gas from said chamber to said garment,means for containing an oxidation catalyst attached to said garment andconnected to said efliuent gas conveying means, and an oxidationcatalyst positioned within said catalyst-containing means.

15. In a suit adapted to be Worn in cold climates and incorporatingprovisions to utilize a chemical reaction to provide heat, a face maskcomprising a face mask housing, breathing gas inlet means and anenclosed chamber attached to said housing, said chamber containing achemical capable of reacting with exhalation to produce a heatedefiiuent gas therefrom, said chemical being selected from the groupconsisting of alkali metals, alkali metal hydrides, and alloys of alkalimetals With metals selected from the group consisting of lead, bismuth,antimony, and tin, said chamber being equipped with means to permit theentrance of said exhalation means to permit the exit of said heatedefliuent gas, a garment, means for containing an oxidation catalystattached to said garment, means for conveying efliuent gas from saidchamber to said catalyst-containing means, and an oxidation catalystpositioned in said catalyst-containing means.

16. A suit comprising a face mask equipped with breathing gas inletmeans, said inlet means providing communication between the interior ofsaid mask and the external atmosphere, an enclosed chamber containing achemical capable of reacting with exahalation to produce a heatedefliuent gas therefrom, said chemical being selected from the groupconsisting of alkali metals, alkali metal hydrides, and alloys of alkalimetals with metals selected from the group consisting of lead, bismuth,antimony, and tin, means to convey exhalation from said face mask tosaid chamber, a garment, means to convey said heated eifluent gas fromsaid chamber to said garment, means for containing an oxidation catalystattached to said garment and connected to said effluent gas-conveyingmeans, and an oxidation catalyst positioned within said catalystcontaining means.

17. In a suit adapted to be Worn in cold climates and incorporatingprovisions to utilize a chemical reaction to provide heat, a face maskcomprising a face mask housing, breathing gas inlet means, said inletmeans providing communication between the interior of said mask and theexternal atmosphere, and an enclosed chamber attached to said housing,said chamber containing a chemical capable of reacting with exhalationto produce a heated efiluent gas therefrom, said chemical being selectedfrom the group consisting of alkali metals, alkali metal hydrides, andalloys of alkali metals with metals selected from the group consistingof lead, bismuth, antimony, and tin, said chamber being equipped withmeans to permit the entrance of said exahalation, means to permit theexit of said heated effiuent gas, a garment, means for containing anoxidation catalyst attached to said garment, means for conveyingeffiuent gas from said chamber to said catalyst-containing means, and anoxidation catalyst positioned in said catalyst-containing means.

References Cited by the Examiner UNITED STATES PATENTS 2,347,583 4/ 1944Vartabedian 2-2.1 2,429,973 11/ 1947 Alexander 126204 2,551,142 5/ 1951Lessard 126204 2,648,325 8/1953 Siple 126-204 2,889,210 6/ 1959 Borard23-4 2,996,062 8/ 1961 Weiss 126208 3,148,034 9/1964 Bovard et al 23-4FOREIGN PATENTS 812,348 2/1937 France.

1,182,262 1/1959 France.

FREDERICK L. MA'ITESON, IR., Primary Examiner.

DAVID J. WILLIAMOWSKY, THOMAS J. HICKEY,

JAMES W. WESTHAVER, Examiners.

1. IN A SUIT ADAPTED TO BE WORN IN COLD CLIMATES AND INCORPORATINGPROVISIONS TO UTILIZE A CHEMICAL REACTION INVOLVING EXHALATION TOPROVIDE HEAT AND PRODUCE AN OXIDIZABLE MATERIAL, A GARMENT, MEANS FORCONTAINING AN OXIDATION CATALYST ATTACHED TO SAID GARMENT, AN OXIDATIONCATA-